Information technologies have known a rapid and a spectacular development leading to an increasing use of electronics and telecommunications in almost all trades and even our daily life. This facilitates information communication and increases efficiency. As a result, our life is more comfortable and our work is more productive Recently, there is a trend of developing slim electronic products among manufacturers. Further, various associated expansion cards are developed. Typically, such expansion cards are inserted in slots of circuit board of an electronic product. Thus, the electronic products are made more powerful.
Many expansion cards such as memory cards, modem cards, or network cards installed in notebook computers are typically Personal Computer Memory Card International Association (PCMCIA) devices. Also, a typical expansion card is about the size of a credit card so that it can be easily inserted in a PCMCIA slot of notebook computer. This is a typical example of slim product today. Another interface specification is PCI available from Intel Corp. PCI defines a local bus system which allows up to 10 PCI devices to install on a computer. Hence, various devices can be incorporated in an electric product. As a result, electronic products can be made slim as well as more powerful.
A bus system used in PCMCIA or PCI is PC Card bus or PCI bus respectively. Both buses are the same in most parts except the followings: PC Card bus has a unique design in a portion thereof so as to insert in a PCMCIA slot. The most significant difference is in data and control signal sent from PCI bus wherein a share bus is the main element in doing this. For example, in slots of desktop computer data buses in first and second slots are served to receive the same group of signals from PCI bus. Hence, a predetermined processing procedure is required in designing the slot so that central processing unit (CPU) of the computer can find a destination of the signals based on command. But as for PC Card bus slots each independently corresponds to a PC Card bus.
An electronic apparatus 2 in a known embedded system is shown in FIG. 1. The apparatus 2 comprises a CPU 22, a memory 23, and a PCI bus 21 served as a path for control and data communication therebetween. In a case that a suitable (either in functions or price) integrated circuit (IC) device is implemented on the apparatus 2 in design phase. If the IC device is originally designed to be used in PC Card bus based system a failure may occur due to bus conflict. In other words, the IC device is allowed to be implemented on PCI bus based apparatus only. Thus, an expansion device compatible to PCI bus has to be redesigned based on needs and PCI bus. This has the drawbacks of money and labor waste, slowing developing time of new electronic products, and reducing efficiency.
Moreover, the apparatus 2 further comprises a PC Card bus compatible IC device 24 being implemented on application PCI bus based apparatus such as the apparatus 2. The apparatus 2 further comprises a bridge IC device 25 on circuit board for adapting PCI bus 21 to PC Card bus. Bridge IC device 25 acts to adapt bus signals of PCI bus 21 to pins of IC device 24 corresponding to PC Card bus. Also, share bus of PCI bus is divided into two portions each coupled to an independent bus compatible to PC Card bus slot. Further, control signals are sent from bridge IC device 25. By utilizing this configuration, PC Card bus compatible ICs are capable of being implemented on application PCI bus based apparatus. However, the prior art suffered from several disadvantages. For example, the apparatus may become bulky (i.e., occupying precious space) due to many pins of the bridge IC device. Total cost is further increased. Moreover, it is neither aesthetic nor slim as contrary to what is expected by consumers. Thus improvement exists in order to overcome the above drawbacks of prior art.